// 
// Entify project
//  
// Author:
//       Lauri Taimila <lauri@taimila.com>
// 
// Copyright (c) 2010 Lauri Taimila
// 
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
// 
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
// 
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.

using System;
using System.Reflection;
using System.Text.RegularExpressions;

namespace Taimila.Entify.Attributes
{
	/// <summary>
	/// Regular expression validator checks does property value match
	/// to validator's regular expression.
	/// </summary>
	[AttributeUsage(AttributeTargets.Property)]
	public sealed class RegularExpressionValidatorAttribute : ValidatorAttribute
	{
		/// <summary>
		/// Regular expression of the validator.
		/// </summary>
		private Regex regularExpression;
		
		/// <summary>
		/// Initializes new regular expression validator with given regular expression.
		/// </summary>
		/// <param name="regularExpression">
		/// Regular expression for the validator. <see cref="System.String"/>
		/// </param>
		public RegularExpressionValidatorAttribute(string regularExpression)
		{
			this.regularExpression = new Regex(regularExpression);
		}
		
		/// <summary>
		/// Tests if specified value matches to validator's regular expression.
		/// </summary>
		/// <param name="property">
		/// Property which value is validated.
		/// </param>
		/// <param name="value">
		/// Value to be validated. <see cref="System.Object"/>
		/// </param>
		/// <returns>
		/// ValidationError or null. <see cref="ValidationError"/>
		/// </returns>
		public override ValidationError ValidateValue(PropertyInfo property, object value)
		{
			if(this.regularExpression.IsMatch(value.ToString()))
			{
				return null;
			}
			else
			{
				return new ValidationError(ValidationErrorReason.StringInvalidFormat, property, property.Name + " is in invalid format.");
			}
		}
	}
}
